-127- 
The Louisiana Agricultural Experiment Station ( 258 ) in 1938 published 
a summary of entomological progress in that State. C. E. Smith reported 
that against the larva derris dust (1,0 percent rotenone) and undiluted 
calcium arsenate were about equal in effectiveness and were superior to 
the other treatments. 
Yfater suspensions and alcoholic extracts of Derris elliptica grown at 
Bangalore, India, were effective. — Mysore, India, Department of Agricul- 
ture ( 287 ) in 1938. 
The North Central States Entomologists ( 309 ) in 1938 discussed the 
control of certain insects by the use of cube and derris. Compton report- 
: ed that there was a heavy infestation of cabbage worms in northern Illi- 
nois in 1937, including this species. Control experiments included tests 
with lead arsenate, calcium arsenate, cryolite, cube, pyrethrum, and 
several proprietary materials, applied by means of a Niagara traction 
duster with trailer or Bean power sprayer. Tests were extended over a 
period of several weeks late in the summer. Rotenone-bearing dusts or 
sprays and lead arsenate dusts or sprays gave the best results. W, H. 
Yiihite remarked that derris and cube dusts control Plutella to some extent, 
if treatment is applied while the worms are in the younger stages. 
Parks and Pierstorff ( 524 ) in 1938 recommended rotenone dust for the 
control of this species. 
Reid and Bare ( 347 ) in 1938 reported that against this species the 
1-percent rotenone and the derris-pyrethrum dust mixture (0.5 percent ro- 
tenone plus 0,2 percent pyrethrins), at 7- or 10- to 11 -day intervals be- 
tween applications, were most effective. 
Roark ( 557 ) in 1938 reviewed the comparative action of derris. and cube 
of equal rotenone content of many insects. Reference was made to Campbell, 
who in 1934, in a typewritten report to the Division of Truck Crop and Gar- 
den Insect Investigations, of the Bureau of Entomology and Plant Quarantine 
of the United States Department of Agriculture, stated that derris dust 
(0.5 percent rotonone) destroyed 58,6 percent and cube dust 60.5 percent 
of the diamondback moth caterpillars. He also referred to Yfelker and Ander- 
son ( 465 ), who in 1935 reported that cube dust did not seem to give quite 
so satisfactory control of these larvae as did a derris dust, but in 1937 
they (469) reported that a derris-Aresket-talc dust gave 82 percent control 
and a cubo-Aresket-talc dust of the same (0.5 percent) rotenone content 
gave 87 percent control. The dusts were applied at the rate of about 25 
pounds per acre. 
The Division of Control Investigations, Bureau of Entomology and Plant 
Quarantine, United States Department of Agriculture ( 444 ) in 1938 reportod 
results of tests with derris and cube on certain insects as follows: 
